In Judaism, there is reward and punishment--but there is more to that idea than the eye sees. There is more to an act than the actual deed, and there is more to its consequence than what we might perceive as rewarding or punishing. 

The Askmoses Answer: 

A. Firstly, Man has free will--like no other creature has. No dog, dolphin or gorilla has the ability to weigh good and evil and choose one over the other. No dog, dolphin or gorilla understands the concepts of good and evil, for that matter. None except Man. So, the Jewish understanding of reward and punishment begins with the Jewish understandings of free choice, and good and evil.

B. Man has Free Choice. You can choose to do good. You can choose to do evil. You can choose. You can. You. G-d doesn't make you go one way or the other. He doesn't force you to the straight and narrow. He does not pre-program you to be a certain way. Man could do whatever he wants. Man can change whatever he is to become whoever he wants to be. Total freedom.

G-d won't... zap you with lightning bolts if you do something He deems evil--would you have Free Choice if He did?

1. Defining Good, Evil, Reward and Punishment

The Torah is mankind's morality manual. The Torah defines what is good and what is evil. When you do what the Torah says, you're doing good. When you don’t do what the Torah says--or when you do what the Torah says not to--you're doing evil. (But that's only if you're familiar with the Torah, and act spitefully against it--more on that later.)

When you do good, you're rewarded, and when you do evil, you're punished. Sounds simple? It's anything but.

There's no Reward and Punishment Catalog in Judaism listing specific sins or good deeds and their specific consequences, and therefore, we don't know which actions elicit which reactions from G-d. Unless you are a prophet, you cannot conclude that Mr. A's son died because Goldberg ate non-Kosher or that Mrs. B got Lou Gehrig's Disease because she's a crook. Conversely, you cannot conclude that Bill Gates is rich because he's a good person (which is not to say he isn't).

2. The World to Come 

In Judaism, there are two planes of existence: the physical, and the spiritual.

The physical existence is this universe. And the spiritual existence is called the World to Come. The World to Come is where you are before you're born, and where you go after you die. If you're good or evil, G-d may reward or punish you here, or He may reward or punish you there--in the World to Come. Or both.

suffering is not always punishment, punishment is not always suffering, good is not always a reward, and evil is not always punishment

It's a form of existence where you're soul is cleansed of any decay that might have attached itself during its physical lifetime. The washing erases all traces of physical existence and restores you to your pristine, pre-birth state of spiritual existence. Once restored, you reconnect with G-d at the level of spirituality attained during physical existence.

The washing is your "punishment," and the reconnecting is your "reward."

3. However great the reward or punishment may be, it should not be one's ultimate motive. Maimonidies¹ describes this as serving G-d out of fear of consequences or anticipation of benefits, thus ultimately, self-concern. Rather, the great sage elaborates, one's relationship with G-d should be built on love--and love is giving, not getting, selflessness, not selfishness.